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First Exclusive Measurement Of Deeply Virtual Compton Scattering Off 4He: Toward The 3d Tomography Of Nuclei, M. Hattawy, N. A. Baltzell, R. Dupré, K. Hafidi, S. Stepanyan, S. Bültmann, R. De Vita, A. El Alaoui, L. El Fassi, H. Egiyan, B. Torayev, D. Adikaram, M. J. Amaryan, G. Charles, M. Khachatryan, A. Klein, S. E. Kuhn, M. Mayer, Y. Prok, L. B. Weinstein, Z. W. Zhao

Physics Faculty Publications

We report on the first measurement of the beam-spin asymmetry in the exclusive process of coherent deeply virtual Compton scattering off a nucleus. The experiment uses the 6 GeV electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident on a pressurized ⁴He gaseous target placed in front of the CEBAF Large Acceptance Spectrometer (CLAS). The scattered electron is detected by CLAS and the photon by a dedicated electromagnetic calorimeter at forward angles. To ensure the exclusivity of the process, a specially designed radial time projection chamber is used to detect the recoiling ^{4 …}

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Rosenbluth Separation Of The Π0 Electroproduction Cross Section Off The Neutron, M. Mazouz, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, S. Koirala, M. N. H. Rashad

Physics Faculty Publications

We report the first longitudinal-transverse separation of the deeply virtual exclusive π⁰ electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions dσ_L/dt, dσ_T/dt, dσ_LT/dt, and dσ_TT/dt are extracted as a function of the momentum transfer to the recoil system at Q² = 1.75 GeV² and x_B = 0.36. The ed -> edπ⁰ cross sections are found compatible with the small values expected from theoretical models. The en -> enπ⁰ cross sections show a dominance from the response to transversely polarized …

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Measurement Of The Τ Lepton Polarization And R(D^{}) In The Decay B[Over ¯]→D^{}Τ^{-}Ν[Over ¯]_{Τ}, S. Hirose Et Al., D. Joffe, Ratnappuli L. Kulasiri

Faculty and Research Publications

We report the first measurement of the τ lepton polarization Pτ (D ∗ ) in the decay B¯ → D ∗ τ −ν¯τ as well as a new measurement of the ratio of the branching fractions R(D ∗ ) = B(B¯ → D ∗ τ −ν¯τ )/B(B¯ → D ∗ ` −ν¯`), where ` − denotes an electron or a muon, and the τ is reconstructed in the modes τ − → π −ντ and τ − → ρ −ντ . We use the full data sample of 772×106 BB¯ pairs recorded with the Belle detector at the KEKB electron-positron …

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Electroproduction Of W Mesons Off Protons In The Third Resonance Region And Beyond, Evan Phelps

Theses and Dissertations

Exclusive electroproduction of ω(782) mesons in the reaction ep → epω → epπ+π−π0 was studied from the production threshold, through the third resonance region, and beyond. With electron beam energies close to 6 GeV, the kinematic range covers W = [1.72, 2.60) GeV and Q2 = [1.85, 5.15) GeV2. By combining two sets of data collected by the Thomas Jefferson National Accelerator Facility’s wide-acceptance spectrometer (CLAS), the largest set of resonance-region differential cross sections, d2σh dΩ∗ , for ω electroproduction have been produced. Response functions RT + LRL, RTT , and RTL were extracted to provide a view of how …

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Target And Beam-Target Spin Asymmetries In Exclusive Pion Electroproduction For Q2 > 1 Gev2 . I. Ep → Eπ+N, P. E. Posted, M. J. Amaryan, S. Anefalos Pereira, H. Avakian, R. A. Badui, J. Ball, N. A. Baltzell, M. Battaglieri, V. Batourine, I. Bedlinsky, S. Bültmann, S. E. Kuhn, B. Torayev, L. B. Weinstein, J. Zhang

Physics Faculty Publications

Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π⁺ electroproduction reaction γ^∗p→nπ⁺. The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic range covered is 1.1 < W < 3 GeV and 1 < Q²< 6 GeV^2. Results were obtained for about 6000 bins in W, Q², cos(θ^∗), and φ^∗. Except at forward angles, very large target-spin asymmetries are observed over the entire W region. Reasonable agreement is found with phenomenological fits to previous …

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Full-Text Articles in Physics

Physics Faculty Publications

Rosenbluth Separation Of The Π0 Electroproduction Cross Section Off The Neutron, M. Mazouz, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, S. Koirala, M. N. H. Rashad

Physics Faculty Publications

Measurement Of The Τ Lepton Polarization And R(D^{}) In The Decay B[Over ¯]→D^{}Τ^{-}Ν[Over ¯]_{Τ}, S. Hirose Et Al., D. Joffe, Ratnappuli L. Kulasiri

Faculty and Research Publications

Electroproduction Of W Mesons Off Protons In The Third Resonance Region And Beyond, Evan Phelps

Theses and Dissertations

Physics Faculty Publications

Full-Text Articles in Physics

Physics Faculty Publications

Rosenbluth Separation Of The Π0 Electroproduction Cross Section Off The Neutron, M. Mazouz, Z. Ahmed, H. Albataineh, K. Allada, K. A. Aniol, V. Bellini, M. Benali, W. Boeglin, P. Bertin, M. Canan, C. E. Hyde, S. Koirala, M. N. H. Rashad

Physics Faculty Publications

Measurement Of The Τ Lepton Polarization And R(D^{*}) In The Decay B[Over ¯]→D^{*}Τ^{-}Ν[Over ¯]_{Τ}, S. Hirose Et Al., D. Joffe, Ratnappuli L. Kulasiri

Faculty and Research Publications

Electroproduction Of W Mesons Off Protons In The Third Resonance Region And Beyond, Evan Phelps

Theses and Dissertations

Physics Faculty Publications

Measurement Of The Τ Lepton Polarization And R(D^{}) In The Decay B[Over ¯]→D^{}Τ^{-}Ν[Over ¯]_{Τ}, S. Hirose Et Al., D. Joffe, Ratnappuli L. Kulasiri